Even Californians who support the legalization of marijuana should be extremely wary of Proposition 19. This is a seriously flawed initiative with contradictions and complications that would invite legal chaos and, more than likely, fail to deliver its promised economic benefits.

We agree with the architects of Prop. 19 that the "war on drugs" - especially as it applies to marijuana - has been an abject failure. Laws against personal possession are widely ignored, they are enforced unevenly and they divert law enforcement and the courts from more pressing priorities. The result is a flourishing underground economy that allows marijuana to escape taxation and regulation while bestowing profits on criminal enterprises.

If this were simply a referendum on the status quo, and the ability of a 21-or-older Californian to possess an ounce or less for personal use, it might be an easy "yes" vote. It is not. It is a law that goes too far in endowing rights for the cultivation, possession and use of marijuana.

Among the specific problems:

Workplace: A nondiscrimination clause would prevent employers from firing or disciplining workers who used marijuana unless an employer could prove that job performance was impaired. Pre-employment testing would be banned. Conflicts with federal law abound. For example, the feds require operators of planes, trains, trucks and buses to be removed from their jobs if they test positive for any narcotic.

Tax and regulation: The measure establishes no state controls over distribution and product standards; it does nothing to help cure the state's budget deficit. A seriously gridlocked Legislature, which kept its distance from the medical marijuana mess, would have to decide whether to take on such issues. In the meantime, Prop. 19 allows the 58 counties and hundreds of cities to come up with their own taxation and regulatory schemes. In this critical element of legalization, Prop. 19 is more akin to the chaotic approach taken with medical marijuana than to the heavily taxed-and-regulated treatment of alcohol.

Cultivation: Property owners throughout the state would have a right to establish a 5-by-5-foot plot of cannabis plants for personal consumption - a right that could not be usurped by local ordinance. Anyone familiar with the stench and potential height of marijuana plants might pause at the thought of their proliferation in the neighborhood.

Transit: The proposition does not affect current laws against driving while impaired by cannabis, but it does allow passengers to smoke in a moving vehicle, proponents acknowledge. This is another element of 219 that that defies common sense.

The experience of Proposition 215, the 1996 initiative that legalized the use of medical marijuana, illustrates the danger of voting for a concept instead of the language of a ballot measure. The loosely drawn Prop. 215 continues to be a nightmare for many communities. Los Angeles is trying to shut down hundreds of dispensaries. Even the laid-back coastal towns of Santa Cruz and Arcata found themselves putting moratoriums on new dispensaries.

Fresno County Supervisors this week voted to ban outdoor medical marijuana gardens after four reports of gunfire - including a fatal shooting by a homeowner who claimed an intruder was out to steal his pot.

If Prop. 19 were to pass, such outdoor gardens would not be limited to ostensible medical-marijuana patients. They could show up in any backyard, in any town - and local governments would be powerless to stop them.